苦橙不同部位挥发油成分及抗氧化与抗菌活性分析

Essential oil components and their antioxidant and antibacterial activities in different parts of Citrus aurantium var.amara

为较全面地研究苦橙(Citrus aurantium var.amara)全植株挥发油成分及抗氧化与抗菌活性,该研究以其叶、花、幼果为材料,采用水蒸气蒸馏法(SD)结合气相色谱-质谱(GC-MS)联用技术分析其成分,并利用体外测试方法比较了三者的抗氧化与抗菌活性。结果表明:(1)从苦橙叶、花、幼果3个部位挥发油中共分离鉴定出94种成分,3个部位的挥发油成分种类及含量存在一定差异,其中13种为共有成分。从叶中鉴定出34种成分,含量较高的有芳樟醇(30.51%)、α-松油醇(14.78%);从花中鉴定出32种成分,主要成分有芳樟醇(57.59%)和d-柠檬烯(16.15%);从幼果中鉴定出69种挥发性成分,主要含有d-柠檬烯(25.55%)和γ-萜品烯(10.48%)。(2)苦橙3个部位挥发油表现出不同程度的抗氧化活性,其中苦橙幼果、叶及花的挥发油对ABTS自由基的IC 50值分别为2.6、5.1、8.2 mg·mL^(-1),对DPPH自由基的IC 50值分别为2.7、4.3、5.0 mg·mL^(-1),幼果挥发油的抗氧化活性最好。(3)苦橙幼果挥发油对大肠杆菌、金黄色葡萄球菌和铜绿假单胞菌表现出的抗菌活性强于叶和花。该研究结果为苦橙叶、花及其幼果中挥发油的提取与利用提供了理论依据。

In order to comprehensively analyze the essential oil components,antioxidant and antibacterial activities of the whole plant of Citrus aurantium var.amara,the essential oils from leaves,flowers and young fruits were extracted respectively by steam distillation(SD)and their chemical compositions were identified by GC-MS.Moreover,their antioxidant and antibacterial activities were evaluated and compared using in vitro methods.The results were as follows:(1)A total of 94 volatile components were isolated and identified from the essential oils of leaves,flowers and young fruits,there were some differences between three parts,of which 13 were common components.A total of 34 components were identified from leaves,and the major compounds were linalool(30.51%)andα-terpineol(14.78%);a total of 32 components were identified from flowers,the main components were linalool(57.59%)and d-limonene(16.15%);a total of 69 components were identified from young fruits,mainly containing d-limonene(25.55%)andγ-terpene(10.48%).(2)The essential oils from different parts showed different antioxidant activities.The IC 50 values of essential oils from young fruits,leaves and flowers to ABTS free radicals were 2.6,5.1 and 8.2 mg·mL^(-1),respectively,and the IC 50 values to DPPH free radicals were 2.7,4.3 and 5.0 mg·mL^(-1),respectively.The antioxidant activity of young fruits was better than that of leaves and flowers.(3)The essential oil from young fruits showed certain antibacterial activity against Escherichia coli,Staphylococcus aureus and Pseudomonas aeruginosa,which was better than the leaves and flowers.The results can provide a theoretical basis for the extraction and utilization of the essential oils from different parts of Citrus aurantium var.amara.